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Thread: Which headers for Magnaflow catback?

  1. #1
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    Default Which headers for Magnaflow catback?

    Hey all
    New here, and new to the G8 world
    Just picked a GT and discovered it has a magnaflow catback exhaust on it.
    Id like to put headers on the as well and was curious is anyone is running a magnaflow cat back and what headers are you using.

    Thank you so much for your time

  2. #2
    VIP Member STL_G8GT's Avatar
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    Quote Originally Posted by SinisterGT View Post
    Hey all
    New here, and new to the G8 world
    Just picked a GT and discovered it has a magnaflow catback exhaust on it.
    Id like to put headers on the as well and was curious is anyone is running a magnaflow cat back and what headers are you using.

    Thank you so much for your time
    You're going to look for headers that would work with the stock catback... I don't know that any will without some work.
    2009 PBM G8 GT
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  3. #3
    Administrator Chewy's Avatar
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    Kooks with the correct adaptors will work. I will warn you, that exhaust will drone you right out of the cabin with headers!

    2009.5 MSM GXP 500ish N/A RWHP. Mods include but aren't limited to: Texas Speed 418 (6.8L) fully forged held together with ARP from top to bottom, PRC 255cc heads, Rick Crawford intake plenum, TB port, polish and tune, Roto-Fab 102mm CAI w/LS7 MAF, Kooks 1-7/8" headers wrapped with DEI, Corsa catless system, Circle D 3200 Stall, 3.45 final drive, BMR's complete street bushing kit and sway bars, Eibach Pro Kit, G-Force Axles, running on staggered VMR 710's with Bridgestone RE11 rubber. HSV triple gauge pack with Calais smokers kit mod, V6 tails, debadge/rebadge, V6 door handles, AU black door trim, Maverick Man under hood strut covers, & washer and bolt kit, fully corrected paint thanks to Adams Polishes and my hard work. Built with reliability in mind with some power for those times when you need to pass or go over a big hill. Just a poser, not a racer!

  4. #4
    VIP Member G8Holland's Avatar
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    Kooks Mid Length headers with cats (Kooks #24201420) will work with a cat back system. I have them and the Magnaflow 16887.

    What Chewy says is right, if you still have the cylinder deactivation active (a.k.a. DOD) the Magnaflows drone bad, especially on the highway. Once that was removed the sound is pretty nice, a little on the low side for some.
    2009.1 PBM GT
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    Baker Engineering Wrenched and Tuned, BMR, Roto-Fab, Magnaflow, Hankook, DBA, Hawk. Kooks, ATI
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  5. #5
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    I have magnaflow cat back with kooks mid length headers which come with HFC's that will bolt right up to the cat back system. Tune will likely be needed for the high flow cats so they don't throw a code. Headers aren't going to change the sound much, speaking from experience.
    I think pypes or ARH or somebody makes long tube headers that will bolt up. If something says it will bolt up to the stock cat-back, it will work since your magnaflow cat back should have the same connections as stock.

    I do agree that DOD should be turned off considering the almost negligible mileage gain and drone this system makes.
    09 GT PBM - Red/Onyx - Sport, Premium, Roof

    Rotofab, LS7 MAF, Pat G, Kooks 1-7/8 Mids w/ HFC's, Magaflow Cat-Back, 3.45 gears

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